The present invention pertains to a sewing machine which is capable of forming more than a single line of stitches by means of a separate needle for each seam or line of stitching and that includes a separate looper operatively associated with each needle which are arranged to actuate in tandem. More particularly the invention pertains to a device for interrupting at least one line of stitching while the other line spaced from and parallel therewith continues to be formed.
Sewing machines with dual needles and independent loopers functioning in tandem with their respective needles are well-known and by means of a selective operating control on such machines, both loopers can be displaced to effect an out-of-phase condition thereof with the paths of their respective needles. Such a condition provides a desired suspension of the formation of both the lines of stitching.
The type of sewing machine described supra is particularly set forth in U.S. Pat. No. 2,292,724 wherein its teachings illustrate and describe means which are adapted to cause both the loopers to rotate through a certain angle to create a delay in the stitch-forming phase with respect to their needles thus causing a cessation of stitch formation. An object of the present invention is to provide this type of sewing machine which is utilized in the garment forming industry with a means whereby it is possible to selectively interrupt the seam being formed by one or the other needle, or by both.